我实际上正在处理这段代码
using System;
using Xamarin.Forms;
using System.Diagnostics;
namespace CryptoUI
{
public class HomePage : Xamarin.Forms.MasterDetailPage
{
public HomePage()
{
// Set up the Master, i.e. the Menu
Label header = new Label
{
Text = "MENU",
Font = Font.SystemFontOfSize(20, FontAttributes.Bold),
HorizontalOptions = LayoutOptions.Center
};
// create an array of the Page names
string[] myPageNames = {
"Main",
"Page 2",
"Page 3",
};
// Create ListView for the Master page.
ListView listView = new ListView
{
ItemsSource = myPageNames,
};
// The Master page is actually the Menu page for us
this.Master = new ContentPage
{
Title = "Test",
Content = new StackLayout
{
Children =
{
header,
listView
},
}
};
// Define a selected handler for the ListView contained in the Master (ie Menu) Page.
listView.ItemSelected += (sender, args) =>
{
// Set the BindingContext of the detail page.
this.Detail.BindingContext = args.SelectedItem;
string currentPage = this.GetType().Name.ToString();
// This is where you would put your “go to one of the selected pages”
if(listView.SelectedItem.Equals("Main") && !currentPage.Equals("HomePage")){
AsyncPush(new HomePage());
}
else if(listView.SelectedItem.Equals("Page 2") && !currentPage.Equals("SecondPage")){
AsyncPush(new SecondPage());
}
else if(listView.SelectedItem.Equals("Page 3") && !currentPage.Equals("ThirdPage")){
AsyncPush(new ThirdPage());
}
// Show the detail page.
this.IsPresented = false;
};
listView.ItemSelected += (senders, e) => {
if (e.SelectedItem == null) return; // don't do anything if we just de-selected the row
// do something with e.SelectedItem
((ListView)senders).SelectedItem = null; // de-select the row
};
// Set up the Detail, i.e the Home or Main page.
Label myHomeHeader = new Label
{
Text = "Home Page",
HorizontalOptions = LayoutOptions.Center
};
string[] homePageItems = { "Alpha", "Beta", "Gamma" };
ListView myHomeView = new ListView {
ItemsSource = homePageItems,
};
var myHomePage = new ContentPage();
myHomePage.Content = new StackLayout
{
Children =
{
myHomeHeader,
myHomeView
} ,
};
this.Detail = myHomePage;
}
public async void AsyncPush(Page page)
{
await Navigation.PushAsync(page);
}
}
}
此代码实际上使用 Xamarin Forms 技术显示了一个简单的 FlyOut 菜单。 我目前正在尝试了解如何在选择要前往的页面后轻松清除 ListView 选择!
我在 Xamarin 的开发者网站上找到了这段代码 ( http://developer.xamarin.com/guides/cross-platform/xamarin-forms/working-with/listview/ );
listView.ItemSelected += (sender, e) => {
if (e.SelectedItem == null) return; // don't do anything if we just de-selected the row
// do something with e.SelectedItem
((ListView)sender).SelectedItem = null; // de-select the row
};
但我目前无法弄清楚我应该如何将它与上面的代码集成:)
最佳答案
我想补充 Jason 的回答,因为它遗漏了一些重要信息。当您将 ListView SelectedItem 属性设置为 null 时,它将再次触发 ItemSelected 事件。所以如果你没有空检查,它会抛出异常。
它应该是这样的:
void ItemSelected(object sender, EventArgs args)
{
if (((ListView)sender).SelectedItem == null)
return;
//Do stuff here with the SelectedItem ...
((ListView)sender).SelectedItem = null;
}
关于c# - Xamarin - 清除 ListView 选择,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/27306685/